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1.
Opt Lett ; 48(12): 3127-3130, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319043

RESUMO

Spatial coherence of light sources is usually obtained by using the classical Young's interferometer. Although the original experiment was improved upon in successive works, some drawbacks still remain. For example, several pairs of points must be used to obtain the complex coherence degree (normalized first-order correlation function) of the source. In this work, a modified Mach-Zehnder interferometer which includes a pair of lenses and is able to measure the spatial coherence degree is presented. With this modified Mach-Zehnder interferometer, it is possible to measure the full 4D spatial coherence function by displacing the incoming beam laterally. To test it, we have measured only a 2D projection (zero shear) of the 4D spatial coherence, which is enough to characterize some types of sources. The setup has no movable parts, making it robust and portable. To test it, the two-dimensional spatial coherence of a high-speed laser with two cavities was measured for different pulse energy values. We observe from the experimental measurements that the complex degree of coherence changes with the selected output energy. Both laser cavities seem to have similar complex coherence degrees for the maximum energy, although it is not symmetrical. Thus, this analysis will allow us to determine the best configuration of the double-cavity laser for interferometric applications. Furthermore, the proposed approach can be applied to any other light sources.


Assuntos
Lasers , Lentes , Interferometria/métodos
2.
J Allergy Clin Immunol ; 108(3): 387-93, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11544458

RESUMO

BACKGROUND: Studies show that nerve growth factor (NGF) exhibits immunomodulatory activity. This neurotrophin is found at high levels in the serum of asthmatic individuals, is released during allergic reactions, and is reported to augment in vitro histamine and leukotriene C4 release by human basophils. OBJECTIVE: Because basophils represent a substantial source of IL-4 and IL-13, we tested the effects of NGF on the secretion of these cytokines by cells prepared from allergic subjects and cells prepared from nonallergic subjects. METHODS: Cytokine and histamine were measured in culture supernatants by ELISA and fluorimetry, respectively. Both real-time RT-PCR and conventional RT-PCR were used to measure IL-13 mRNA expression. NGF receptor expression was determined by 2-color flow cytometry. RESULTS: Basophil suspensions from allergic subjects secreted some 2.5-fold greater levels of IL-13 when cultured with NGF than did cells prepared from normal control subjects. Flow cytometry revealed no significant differences in TrkA receptors on basophils to explain these findings. The levels of IL-13 secreted by the 2 groups of donors also differed when cells were activated with IL-3 but not when they were activated with anti-IgE antibody. Both NGF and IL-3 failed to induce IL-13 in cell cultures depleted of basophils, suggesting that the measurable IL-13 was indeed basophil-derived. Real-time RT-PCR showed an average induction of IL-13 message above medium control that was 4.3 (+/- 1.7)-fold with NGF and 8.9 (+/- 3.7)-fold with IL-3. Finally, NGF priming resulted in a remarkable enhancement of IL-13 induced by anti-IgE. This was significantly greater than the priming observed for either the IL-4 or histamine when this stimulus was used. CONCLUSION: NGF (like IL-3) can both directly stimulate IL-13 secretion and modulate IgE-mediated responses in basophils. Its enhanced effect on cells from allergic individuals raises the importance of this cytokine in the pathogenesis of allergic disease.


Assuntos
Basófilos/efeitos dos fármacos , Hipersensibilidade/imunologia , Interleucina-13/metabolismo , Interleucina-3/farmacologia , Fator de Crescimento Neural/farmacologia , Adjuvantes Imunológicos/farmacologia , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Humanos , Interleucina-13/genética , RNA Mensageiro/biossíntese , Receptor trkA/análise
3.
J Allergy Clin Immunol ; 107(2): 265-71, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11174192

RESUMO

BACKGROUND: Human blood basophils secrete high levels of IL-4 following activation with specific allergen, yet their role as cytokine-producing cells in allergic lesions has not been described. OBJECTIVE: Our objective was to investigate whether and under what conditions basophils infiltrating allergic lesions in the lung secrete IL-4 in vitro. METHODS: Bronchoalveolar lavage (BAL) cells were recovered 20 hours after segmental allergen challenge. Basophils were enriched with Percoll using a protocol commonly used for blood basophils. IL-4 and histamine were measured in culture supernatants following activation with a variety of stimuli. Two-color flow cytometry was performed to detect intracellular IL-4. RESULTS: IL-4 protein was detected in all basophil culture supernatants following a 4- to 5-hour incubation in medium alone; the levels obtained did not significantly increase with the addition of anti-IgE. BAL basophils failed to release histamine in response to specific allergen but showed nearly 60% histamine release with N-formyl-methionyl-leucyl-phenylalanine, suggesting that they were desensitized to IgE-mediated stimuli as a result of their activation in vivo. Using these same conditions, IL-4 was not detected in BAL cell fractions enriched for lymphocytes and eosinophils. Ionomycin induced IL-4 secretion by BAL basophils, and this response was reduced with the addition of phorbol myristate acetate. In contrast, phorbol myristate acetate promoted the secretion of IL-4 by BAL cells enriched for lymphocytes; both findings are identical to those reported for basophils and lymphocytes purified from blood. Flow cytometry confirmed the secretion of IL-4 by BAL basophils. CONCLUSIONS: These data suggest that basophils migrating to the lung following allergen challenge represent a major source of IL-4.


Assuntos
Alérgenos/farmacologia , Basófilos/metabolismo , Interleucina-4/metabolismo , Pulmão/citologia , Basófilos/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/citologia , Citometria de Fluxo , Humanos , Pulmão/imunologia , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo
5.
Am J Phys Anthropol ; 51(3): 389-92, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-532824

RESUMO

An example is reported of a rare dermatoglyphic variant (absence of triradius d) in a woman of mixed European and Cherokee American Indian ancestry. This variant was not present in her parents, her five siblings, four nephews or one niece. Attention is drawn to the continuum from an absent triradius d to a triradius with an abbreviated main-line associated with either an open field in interdigital area IV, or a loop in interdigital area IV or a tented arch at d. This same continuum occurs at c. The absent triradius at d is extremely rare and the tented arch at d is very rare.


Assuntos
Dermatoglifia , Genes , Feminino , Humanos , Masculino , Linhagem
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